A collage of images from the FUV instrument. The images were acquired simultaneously and show the northern aurora at three different wavelengths. The top image was obtained with the FUV Wideband Imaging Camera (WIC) and shows auroral emissions from molecular nitrogen that has been excited by precipitating energetic electrons (ring-shaped structure in the upper right). The bottom-left image shows the aurora produced by precipitating protons. The proton aurora was imaged with the FUV Spectrographic Imager (SI), which detects Doppler-shifted Lyman alpha emissions from neutral hydrogen produced through charge-exchange reactions between the precipitating protons and the neutral gases of the Earth's upper atmosphere. The SI also images auroral oxygen emissions excited by precipitating electrons (bottom right). Although these first images are rather raw, they illustrate well the capabilities of the FUV instrument. For a collage of WIC images showingt the development of the northern aurora over a fifteen-minute period, click here.
Credit: S. Mende and H. Frey, Space Sciences Laboratory, Univ. of California, Berkeley.